The invention relates to an open end friction spinning machine having spinning units with two friction rollers driven in the same direction and arranged adjacent to one another to form a wedge shaped gap within which fibers are spun to form yarn or thread. The spinning units of the type contemplated by the invention also include opening apparatus for opening or separating fiber material to be processed and a fiber feed channel opening oppositely of one of the cover surfaces of at least one of the rollers designed as a suction roller. Yarn or thread withdrawl apparatus for withdrawing the formed yarn in the direction of the wedge is also provided for each spinning unit. The rollers are enclosed by a housing in which the feed channel extends.
With an open end friction spinning apparatus of the abovementioned kind dislosed in DE-OS (German published application) No. 27 14 089, both rollers are completely enclosed by a housing which is connected to a vacuum or under pressure source. It should thereby be achieved that there exists a stepwise decreasing graduation of the vacuum pressure between the region of the fiber inlet and opening apparatus, the fiber feeding channel, the housing, and the inside of the suction rollers. With an open end friction spinning machine of the indicated kind, the maintenance is especially problematical because it becomes necessary to have free access to at least portions of the friction rollers, and especially in the region of the wedge slot, for example, after a thread break.
The present invention is based upon the problem to so construct an open end friction spinning machine of the abovedescribed kind, that there is a good protection against the penetration of contamination, especially fiber fly, which can decisively hinder the spinning process, while at the same time, however, not decreasing/hindering the maintenance possibilities.
These problems are thereby solved by this invention by providing that the housing is divided into two housing parts approximately in the plane of the separation line between the axes of the rollers and wherein the housing part at the side opposite of the feed channel is arranged at the machine frame and the other housing part is formed as a removable cover which includes an inlet guide portion of the fiber feed channel.
With this construction, it is possible in a simple manner with a simple hand grip to selectively gain free access to the rollers and especially the wedge slot, while also maintaining a good protection against the penetration of contaminants into the vacuum pressure regions.
In an advantageous form of the invention, it is proposed that the two housing parts only surround and enclose the circumferential yarn forming surface portions of the rollers and leave the front sides of the rollers free. In order to adequately prevent the penetration of the contaminants it is sufficient to only cover the circumferential surface of the rollers in the region where the vacuum pressure occurs. It has been learned according to the invention that it is not necessary to provide a completely closed housing.
In further preferred embodiments of the invention, the housing part which is arranged stationarily on the machine frame extends or protrudes over the facing sides of the rollers and is provided with bearing receptacles for the rollers. This arrangement results in an especially advantageous design of the construction.
In advantageous preferred embodiments of the invention, it is further provided that the housing part formed as a cover is pivotably mounted at a pivot axle. Thereby, it is further assured according to the invention, that the cover can be returned from the maintenance position into the driving position without adjustments being necessary. The parts that operate together during the spinning process remain adjusted with respect to one another. In especially advantageous embodiments, the cover is held with a pivot axle at the stationary housing part. Thereby it is assured that the housing parts remain exactly disposed with respect to one another and that also, especially when the rollers are carried by bearings in the stationary housing part, exact alignment of the cover with respect to the rollers is maintained.
In preferred embodiments of the invention it is provided that the inner contour of the cover part of the housing is shaped to conform to the coated surfaces of the rollers which are covered by the cover when in the closed position.
Further objects, features, and advantages of the present invention will become more apparent from the following description when taken with the accompanying drawings which show, for purposes of illustration only, embodiments in accordance with the present invention.